Catalytic asymmetric total syntheses of sesquiterpenoids, (+)- and ( )-ar-macrocarpene
作者:Arindam Khatua、Avishek Roy、Vishnumaya Bisai
DOI:10.1016/j.tet.2019.130918
日期:2020.2
Concise catalytic asymmetric totalsyntheses of aromatic sesquiterpenes, naturally occurring (+)-ar-macrocarpene (1) and unnatural (−)-ar-macrocarpene (ent-1) have been featured (6 steps, ∼60–61% overall yields) from commercially available 4,4-dimethylcyclohex-2-enone 16. The enantioenriched allyl alcohol 12 is obtained from catalytic enantioselective reduction of enone 13b using Corey-Bakshi-Shibata
catalytic asymmetric total synthesis of a sesquiterpene, (+)-ar-macrocarpene (1), in 7 steps with 42.1% overall yields from commercially available inexpensive 5,5-dimethylcyclohexane 1,3-dione. This strategy relies on a key [3,3]-sigmatropic rearrangement effecting reductive transposition through allylic diazene rearrangement (ADR) in a single step from intermediate allylic alcohol (+)-12 under the Mitsunobu
Formal Total Syntheses of (+)- and (-)-<i>ar</i>
-Macrocarpene via Rh<sup>(I)</sup>
-BINAP Catalyzed Conjugate Addition
作者:Arindam Khatua、Souvik Pal、Vishnumaya Bisai
DOI:10.1002/ejoc.202000100
日期:2020.5.3
Formal Total syntheses of both the enantiomers of ar‐Macrocarpene has been described via a key Rh(I)‐BINAP catalyzed p‐tolyl boronic acid addition to substituted 2‐cyclohexenone (up to 94 % yield and 96 % ee). Rh(I)‐(S)‐BINAP provided intermediate (S)‐5,5‐dimethyl‐3‐(p‐tolyl)‐cyclohexanone for naturally occurring (+)‐ar‐Macrocarpene, whereas the antipode of catalyst, Rh(I)‐(R)‐BINAP afforded (R)‐5